全文获取类型
收费全文 | 1498215篇 |
免费 | 323823篇 |
国内免费 | 38574篇 |
专业分类
耳鼻咽喉 | 20340篇 |
儿科学 | 47852篇 |
妇产科学 | 36811篇 |
基础医学 | 251879篇 |
口腔科学 | 35625篇 |
临床医学 | 161491篇 |
内科学 | 333649篇 |
皮肤病学 | 31772篇 |
神经病学 | 118974篇 |
特种医学 | 59240篇 |
外国民族医学 | 660篇 |
外科学 | 231589篇 |
综合类 | 76199篇 |
现状与发展 | 1篇 |
一般理论 | 379篇 |
预防医学 | 131329篇 |
眼科学 | 44782篇 |
药学 | 146950篇 |
5篇 | |
中国医学 | 49082篇 |
肿瘤学 | 82003篇 |
出版年
2019年 | 22186篇 |
2018年 | 26695篇 |
2017年 | 24217篇 |
2016年 | 23728篇 |
2015年 | 25026篇 |
2014年 | 29505篇 |
2013年 | 38393篇 |
2012年 | 47846篇 |
2011年 | 51378篇 |
2010年 | 38674篇 |
2009年 | 44458篇 |
2008年 | 47845篇 |
2007年 | 47133篇 |
2006年 | 46802篇 |
2005年 | 45673篇 |
2004年 | 46809篇 |
2003年 | 44934篇 |
2002年 | 44327篇 |
2001年 | 73983篇 |
2000年 | 72564篇 |
1999年 | 66878篇 |
1998年 | 26485篇 |
1997年 | 24478篇 |
1996年 | 25304篇 |
1995年 | 24758篇 |
1994年 | 23837篇 |
1993年 | 22001篇 |
1992年 | 54236篇 |
1991年 | 52762篇 |
1990年 | 50583篇 |
1989年 | 48463篇 |
1988年 | 44932篇 |
1987年 | 43735篇 |
1986年 | 40813篇 |
1985年 | 38686篇 |
1984年 | 29119篇 |
1983年 | 25321篇 |
1982年 | 17697篇 |
1981年 | 16234篇 |
1980年 | 14873篇 |
1979年 | 26586篇 |
1978年 | 19475篇 |
1977年 | 17452篇 |
1976年 | 16226篇 |
1975年 | 16959篇 |
1974年 | 18881篇 |
1973年 | 18110篇 |
1972年 | 16957篇 |
1971年 | 15204篇 |
1970年 | 14385篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
71.
目的 探讨电针复合靶控输注(Target Controlled Infusion, TCI)在单肺通气食管癌开胸手术麻醉中的应用价值。方法 选取于我院拟行单肺通气食管癌开胸切除手术患者60例作为研究对象。随机将其分为试验组与对照组,对照组30例采取气管插管全麻及TCI靶控输注维持麻醉深度,试验组30例则在对照组方案基础上辅助电针麻醉,记录两组患者手术麻醉时间、药物用量、苏醒时间、并发症;以及术前(TⅠ)、插管前即刻(TⅡ)、插管后1 min(TⅢ)、切皮即刻(TⅣ)、去骨时(TⅤ)、拔管即刻(TⅥ)时平均动脉压(MAP)、平均心率(HR)、BIS值;术前、术后1天、术后3天简易智能精神状态检查量表(MMSE);并于麻醉诱导前(T0)、手术开始2 h(T1)、术后1天(T2)、术后3天(T3)时抽取患者外周静脉血检测IL-1β、IL-6、IL-10、TNF-α浓度。结果 试验组手术用时、麻醉时间略低于对照组,但差异无统计学意义(P>0.05),试验组异丙酚、舒芬太尼用量以及苏醒时间均明显低于对照组(P<0.05);TⅡ时两组平均动脉压(Mean Arterial Pressure, MAP)、心率(Heartrate, HR)较术前明显降低,且试验组MAP明显低于对照组(P<0.05),但两组TⅡ时HR比较无显著差异(P>0.05);TⅢ、TⅥ时对照组MAP、HR明显高于TⅠ时,而试验组MAP、HR与TⅠ比较无显著差异(P>0.05)。术后1天、3天试验组简易智能精神状态检查量表(Mini-Mental State Examination, MMSE)评分低于对照组,有显著性差异(P<0.05)。T1、T2、T3时试验组白介素-1β(IL-1β)、白介素-6(IL-6)、肿瘤坏死因子(Tumor Necrosis Factor-α, TNF-α)水平明显低于对照组(P<0.05),白介素-10(IL-10)水平明显高于对照组(P<0.05)。结论 采用电针复合TCI靶控输注麻醉方案可有效提升单肺通气食管癌开胸手术麻醉效果,能够降低患者术后认知功能障碍发生风险。 相似文献
72.
Adilson Cunha Ferreira Edward Araujo Júnior Wellington P. Martins João Francisco Jordão Antônio Hélio Oliani Simon E. Meagher 《The journal of maternal-fetal & neonatal medicine》2015,28(14):1706-1710
Objective: To assess the quality of images and video clips of fetal central nervous (CNS) structures obtained by ultrasound and transmitted via tele-ultrasound from Brazil to Australia.Methods: In this cross-sectional study, 15 normal singleton pregnant women between 20 and 26 weeks were selected. Fetal CNS structures were obtained by images and video clips. The exams were transmitted in real-time using a broadband internet and an inexpensive video streaming device. Four blinded examiners evaluated the quality of the exams using the Likert scale. We calculated the mean, standard deviation, mean difference, and p values were obtained from paired t tests.Results: The quality of the original video clips was slightly better than that observed by the transmitted video clips; mean difference considering all observers = 0.23 points. In 47/60 comparisons (78.3%; 95% CI?=?66.4–86.9%) the quality of the video clips were judged to be the same. In 182/240 still images (75.8%; 95% CI?=?70.0–80.8%) the scores of transmitted image were considered the same as the original.Conclusion: We demonstrated that long distance tele-ultrasound transmission of fetal CNS structures using an inexpensive video streaming device provided images of subjective good quality. 相似文献
73.
74.
75.
Parallel enzyme‐linked immunosorbent assay screening for human immunodeficiency virus among blood donors in five Chinese blood centres: a retrospective analysis 下载免费PDF全文
76.
77.
Kui Li Jiawen Wang Shengxiong Liu Sen Su Chenjian Feng Xiaoxiang Fan Zhiyong Yin 《中华创伤杂志(英文版)》2015,18(2):65-73
Objective: To study the biomechanical mechanism of head injuries beaten with sticks, which is common in the battery or assaultive cases.
Methods: In this study, the Hybrid-III anthropomorphic test device and finite element model (FEM) of the total human model for safety (THUMS) head were used to determine the biomechanical response of head while being beaten with different sticks. Total eight Hybrid-III tests and four finite element simulations were conducted. The contact force, resultant acceleration of head center of gravity, intracranial pressure and von Mises stress were calculated to determine the different biomechanical behavior of head with beaten by different sticks.
Results: In Hybrid-III tests, the stick in each group demonstrated the similar kinematic behavior under the same loading condition. The peak values of the resultant acceleration for thick iron stick group, thin iron stick group, thick wooden stick group and thin wooden stick group were 203.4 g, 221.1 g, 170.5 g and 122.2 g respectively. In finite element simulations, positive intracranial pressure was initially observed in the frontal comparing with negative intracranial pressure in the contra-coup site. Subsequently the intracranial pressure in the coup site was decreasing toward negative value while the contra-coup intracranial pressure increasing toward positive values.
Conclusions: The results illustrated that the stiffer and larger the stick was, the higher the von Mises stress, contact force and intracranial pressure were. We believed that the results in the Hybrid-III tests and THUMS head simulations for brain injury beaten with sticks could be reliable and useful for better understanding the injury mechanism. 相似文献
78.
To determine the protective effect of aloe-emodin (AE) from high glucose induced toxicity in RIN-5F (pancreatic β-cell) cell and restoration of its function was analyzed. RIN-5F cells have been cultured in high glucose (25 mM glucose) condition, with and without AE treatment. RIN-5F cells cultured in high glucose decreased cell viability and increased ROS levels after 48 hr compared with standard medium (5.5 mM glucose). Glucotoxicity was confirmed by significantly increased ROS production, increased pro-inflammatory (IFN-γ, IL-1β,) & decreased anti-inflammatory (IL-6&IL-10) cytokine levels, increased DNA fragmentation. In addition, we found increased Bax, caspase 3, Fadd, and Fas and significantly reduced Bcl-2 expression after 48 hr. RIN-5F treated with both high glucose and AE (20 μM) decreased ROS generation and prevent RIN-5F cell from glucotoxicity. In addition, AE treated cells cultured in high glucose were transferred to standard medium, normal responsiveness to glucose was restored within 8hr and normal basal insulin release within 24 hr was achieved when compared to high glucose. 相似文献
79.
80.